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Topic Review (Newest First)

12-03-2012 01:18 AM

HD Blazingwolf

while we are at it
Tom, i've heard you modify tamm's to act as needle wheel's before ur return pump

That is a very interesting and thought provoking theory Tom. I really never thought of the high amounts of dissolved air/gasses adhere to surfaces and pulling off films that could/would lead to algae. Makes sense that the plants we keep(most of which are not constantly submersed) would benefit from being exposed to the air on a regular basis. The huge weekly water change has always been a part of my aquarium maintence routine, as that is what I did when I kept reef tanks and that is what my dad did 25+ years ago when he was breeding fish. People need to start to understand the importance of constantly adding clean/new water to an enclosed system.

Well you could argue the counter to the mist idea as Gerry and few others, and myself are speculating.

That the mist pulls up the "good" periphyton that protects against algae spores(at least some/certain species) and things you'd rather not grow on the plants. Extra cellular polymers(ECTs) are excreted by bacteria on these periphyton films on leaves, these can slough off natural and reduce turbidity, enhance water clarity. Reducing mist but not 100% reduction , can enhance clarity and perhaps preserves some.most of the good periptyon that acts as a protectorant to algae colonization.

Unhealthly plant leaves, do not support a "good" periphyton community and too much CO2 mist might damage the periphyton a little bit.

So a mix of the of a little bit of mist with the improved water clarity seems to be ideal based on observations blending needle wheel and reactors together to minimize the mist entering the tank, but not having the reactor fill up with gas later in the day.

The periphyton films may be what helps plants dominate in rich nutrients against algae. And to have healthy "good" periphyton.....you need healthy plants.

Quote:

The CO2 mist hypothesis is making me think about running my CO2 straight from my needle wheel back into the tank again but I can't get used to the millions of bubbles. I get a quite a few micro bubbles in the tank now just by having the reactor return pointed at the main return pump but nowhere close to when it was being fed into the tank.

See Gerry's thread on BR.
I do this pretty much is more round about ways, my return lines are 6-10 ft long and go through other devices etc. So in effect, they have the same result.

I could perhaps maximize things a bit more by adding a reactor post return.
I've done this on some client tanks due to their larger size, the mist is not very visible in my 180 and 120 etc.

You can see the video and no one notices the mist there.

Quote:

Some people you do have to hit it the head with a brick. It doesn't work just to tap people on the shoulder anymore to get their attention.

Only a receptive mind is able to learn. I'm not going to waste my breath on the others.

Another idea might have to do with the water level change makes a pressure differential in the cells. When you lower the water level, the pressure on the cells goes down and "stuff" from inside the cell is expelled (unless it is perfectly elastic). When the water level goes back up, the pressure differential forces "stuff" from the water column into the cells.

The cells do that on their own anyway don't they? Maybe the water change just supercharges it.

Same thing happens with a sponge when you push it down deep into the water and then remove it, then re submerge it again.

Another idea might have to do with the water level change makes a pressure differential in the cells. When you lower the water level, the pressure on the cells goes down and "stuff" from inside the cell is expelled (unless it is perfectly elastic). When the water level goes back up, the pressure differential forces "stuff" from the water column into the cells.

The cells do that on their own anyway don't they? Maybe the water change just supercharges it.

That sounds testable in a 2L bottle with a bunch of riccia. Those take a surprising amount of pressure before they burst. Then you could do it without actually changing water.

12-02-2012 04:23 AM

starquestMM

Another idea might have to do with the water level change makes a pressure differential in the cells. When you lower the water level, the pressure on the cells goes down and "stuff" from inside the cell is expelled (unless it is perfectly elastic). When the water level goes back up, the pressure differential forces "stuff" from the water column into the cells.

The cells do that on their own anyway don't they? Maybe the water change just supercharges it.

12-01-2012 08:16 PM

jccaclimber

Here's another piece of evidence for our puzzle. Today I did a large water change (~80%) in my 75 (which has a 29 gallon sump). I did the water change a couple hours before the lights came on, used pure RO water, and forgot to add the ferts. I came back a couple hours later (just after the lights came on) and noticed all of the plants covered in bubbles, leaves open, etc. One error I made is that since the RO water is stored in a large vat in my basement it was ~67*F rather than the ~75 my tank stays at.

I must say as for myself, I am not quite convinced one way or the other. Are frequent water changes really better?

This summer in my ancient apartment, i had cyanobacteria booms after water changes, maybe it was the tap water there or the fact that water was hot in the summer?

Anyway thank you for sharing this article from Barr's Report. It is very interesting.

Michel.

big water changes are beneficial whether its a fast growing tank with lots of fishies or a tank that is slower going. the slower growth tank however will be more forgiving in the long run
on tanks that recieve less fertilizing, feeding, have lower stocking levels and slower growth, frequent water chagnes aren't as necessary as the system is slow enough to respond to everything happening. plus not much is being added to the tank that needs to be later removed

11-29-2012 02:29 PM

micheljq

Hello, there is also this article from PPS-Pro, which seems to contradict the frequent water changes thinking :

I'm actually serious. We really don't know for sure why fresh water is so beneficial. When we don't know how something is accomplished to me it's magic. There could be elements in fresh water that we can't even measure.

I have one client who has about 10% per day done on automation, generally about 1 hour after the lights come on, then doses CO2 and Excel....as a back up.

The Dosing tanks are 2 x 5 gallons and then 2 x 2.5 Gal back ups.
Carbon block for the tap.

This system has run for about 2 years now.

I come about once every 4-6 months and trim the tank. It's never had any algae issues nor was cleaned. Just fed the fish, algae magnet the front glass once every month or so.

Not bad.

I tend to do my water changes large and frequent in the morning maybe 1 hour after the lights come on. Add ferts back right away etc.
Mad pearling later at night.

This pearling is not on the glass, heater or any other equipment/non live material.
I can easily fluff the bubbles off about 1 hour after the water change and they do not come back(these are degassing bubbles due to high pressure and temp).
At higher pressure and lower temp, the CO2 is higher than at ambient.

If you take this tap water and let it sit for a few minutes, warm up and depressurize........ the CO2 and O2 will escape.
Same for the aquarium.

I think perhaps Ole's work with gas films might apply a bit, it would increase the rates. If you doubt that water changes influence growth rates in your aquarium: a simple test: do water changes daily about 1 hour after the lights come on, say 40-50%. Do this for 1-2 weeks and then do do ANY for 1-2 weeks. See what you think. One day may be hard to tell the differences.

O2 meter does not lie as far as plant growth near the end of the day. It's always higher the day of the water change.
Since I do the water change early on, then 6-7 hours later, the O2 reading is taken.........a direct relationship with the tap is not likely, I also have wet/dry filters which should remove some of the excesses/degassing from the tap, leaving mostly only plant growth production left.

7. Bacterial and periphyton films. As these are exposed to air during the water changes, or high rates of micro bubbles and dissolved air/gases etc..........the bubbles will adhere. They will provide these films with brief high levels of O2, increasing respiration. Some of the surface tension will stick and pull off a lot of these films on plant leaves....... leaving a cleaner plant leaf behind. In the next few hours, the leaves will be recolonized again. This reduces the barrier and increases the Flux across the leaf for nutrients and CO2, light etc.

This may tie into the CO2 mist Hypothesis effect, the mist itself may be doing a cleaning action on the plant leaves.
A water change may also do a very similar thing.

That is a very interesting and thought provoking theory Tom. I really never thought of the high amounts of dissolved air/gasses adhere to surfaces and pulling off films that could/would lead to algae. Makes sense that the plants we keep(most of which are not constantly submersed) would benefit from being exposed to the air on a regular basis. The huge weekly water change has always been a part of my aquarium maintence routine, as that is what I did when I kept reef tanks and that is what my dad did 25+ years ago when he was breeding fish. People need to start to understand the importance of constantly adding clean/new water to an enclosed system.

I change the water in my tank closer to lights out because that is the only time I can do it is after the kids go to bed. I do see an increase in pearling a couple hours after water change but it's lights out about 3 hours after I get done with the water change. So is it to be expected that it would be more beneficial to do water changes early in the light cycle versus later.

The CO2 mist hypothesis is making me think about running my CO2 straight from my needle wheel back into the tank again but I can't get used to the millions of bubbles. I get a quite a few micro bubbles in the tank now just by having the reactor return pointed at the main return pump but nowhere close to when it was being fed into the tank.

Lots of magic in fresh water isn't there. Plants pearl, fish spawn, life is sustained. You don't have to hit me in the head with a brick that says "Do a water change"

Some people you do have to hit it the head with a brick. It doesn't work just to tap people on the shoulder anymore to get their attention.

11-29-2012 04:47 AM

jccaclimber

Unfortunately I don't have much to add to this, but I do think it is an interesting discussion. I too have noticed that plants seem to have their leaves out a bit more later in the day after water changes. When I switched to mainly RO water (~15% tap, sitting out for several days) I expected it to go away, but it didn't. There isn't much in my water, but the plants are exposed to air for a while and there is a ton of splashing when I put the new water in. Perhaps several of these conclusions are valid which is why removing just one doesn't stop the phenomenon?

ur probably right, its due to being exposed to air.
i so badly wanna think that they just like clean water though... maybe just cause i like water change day so much

Good way to create a myth

Even in Dupla's Optimum aquarium, while they give such data for natural systems, they also make a clear point it is impractical to continuously exchange the water and dose small amounts. And the fact of the matter is that it does not help to set things up and do so.

Swimming down the Ichetcuknee river, with a Tier 1 Spring flow, plants abound, but so does algae.

What controls the algae?
Mostly three things: light, light and light.

So even the best systems will have algae, it's just like nature though, to have a specific garden, you need to weed and select out what you like and dislike while nature tries to add it back again.